bug#53749: 29.0.50; [PATCH] Xref backend for TeX buffers

[David Fussner via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Hi Augusto,

For what it's worth, I've always just done what Arash suggests when
RefTeX gets out of sync, and haven't had any issues with it that I can
remember.  (To be fair, my use cases haven't exactly been exotic.)

> The problem is that there's no way for Emacs to communicate that one of
> these programming modes is to be used.  This could be fixed in two ways:
>
> A. by creating latex-prog and latex-expl3 derived modes in Emacs, or
>
> B. adding heuristics to Digestif to decide if a given file is "document"
>    or "code".
>
> Do you have any thoughts about A?  Would there be any other benefits in
> Emacs to justify the latex-prog and latex-expl3 major modes?  It seems
> that (at least in AUCTeX) @ is always considered a letter, which may be
> innocuous but is kinda wrong.

The only thought I have is that it sounds like a new major mode would
be overkill for what you need here.  I would think that a variable or
defcustom might do the trick, or at most maybe a minor mode?  When
navigating code I really want to be able to follow the commands to
their source no matter whether the command is internal or for users,
though I can see how in a code-completion setting you might want to be
able to separate the two more cleanly.  Obviously, I'm not the person
you need to convince about all of this -- that would be Arash and the
emacs maintainers, themselves.

Best,

David.

On Sun, 27 Feb 2022 at 18:43, Arash Esbati <arash@gnu.org> wrote:
>
> Augusto Stoffel <arstoffel@gmail.com> writes:
>
> > If you type \label{something}, as opposed to using the RefTeX command
> > to add a label (or if you edit the label by hand) then RefTeX will not
> > reparse the document and get out of sync.
>
> If you know the known labels to RefTeX are out of sync, you can issue
> `C-c )' with a prefix argument:
>
> ,----[ C-h f reftex-reference RET ]
> | reftex-reference is an interactive native compiled Lisp function in
> | ‘reftex-ref.el’.
> |
> | (reftex-reference &optional TYPE NO-INSERT CUT)
> |
> | Make a LaTeX reference.  Look only for labels of a certain TYPE.
> | With prefix arg, force to rescan buffer for labels.  This should only be
> | necessary if you have recently entered labels yourself without using
> | reftex-label.  Rescanning of the buffer can also be requested from the
> | label selection menu.
> | The function returns the selected label or nil.
> | If NO-INSERT is non-nil, do not insert \ref command, just return label.
> | When called with 2 C-u prefix args, disable magic word recognition.
> |
> |   Probably introduced at or before Emacs version 20.1.
> |
> `----
>
> Or in the labels *RefTeX select* buffer, you have these choices:
>
>  r / C-u r  Reparse document / Reparse entire document.
>
> I usually hit r when I don't find the label I'm looking for.
>
> > Or at least that was the case when I still used RefTeX.  So it might
> > be worth considering some cache invalidation scheme there.
>
> The question is if it's worth the effort where a remedy is already in
> place.
>
> Best, Arash